# Protocol Buffers - Google's data interchange format
# Copyright 2008 Google Inc.  All rights reserved.
# https://developers.google.com/protocol-buffers/
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
#     * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
#     * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

"""Contains routines for printing protocol messages in JSON format.

Simple usage example:

  # Create a proto object and serialize it to a json format string.
  message = my_proto_pb2.MyMessage(foo='bar')
  json_string = json_format.MessageToJson(message)

  # Parse a json format string to proto object.
  message = json_format.Parse(json_string, my_proto_pb2.MyMessage())
"""

__author__ = 'jieluo@google.com (Jie Luo)'

import base64
from collections import OrderedDict
import json
import math
from operator import methodcaller
import re
import sys

from lark_oapi.ws.pb.google.protobuf.internal import type_checkers
from lark_oapi.ws.pb.google.protobuf import descriptor
from lark_oapi.ws.pb.google.protobuf import symbol_database

_TIMESTAMPFOMAT = '%Y-%m-%dT%H:%M:%S'
_INT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT32,
                        descriptor.FieldDescriptor.CPPTYPE_UINT32,
                        descriptor.FieldDescriptor.CPPTYPE_INT64,
                        descriptor.FieldDescriptor.CPPTYPE_UINT64])
_INT64_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_INT64,
                          descriptor.FieldDescriptor.CPPTYPE_UINT64])
_FLOAT_TYPES = frozenset([descriptor.FieldDescriptor.CPPTYPE_FLOAT,
                          descriptor.FieldDescriptor.CPPTYPE_DOUBLE])
_INFINITY = 'Infinity'
_NEG_INFINITY = '-Infinity'
_NAN = 'NaN'

_UNPAIRED_SURROGATE_PATTERN = re.compile(
    u'[\ud800-\udbff](?![\udc00-\udfff])|(?<![\ud800-\udbff])[\udc00-\udfff]')

_VALID_EXTENSION_NAME = re.compile(r'\[[a-zA-Z0-9\._]*\]$')


class Error(Exception):
    """Top-level module error for json_format."""


class SerializeToJsonError(Error):
    """Thrown if serialization to JSON fails."""


class ParseError(Error):
    """Thrown in case of parsing error."""


def MessageToJson(
        message,
        including_default_value_fields=False,
        preserving_proto_field_name=False,
        indent=2,
        sort_keys=False,
        use_integers_for_enums=False,
        descriptor_pool=None,
        float_precision=None,
        ensure_ascii=True):
    """Converts protobuf message to JSON format.

    Args:
      message: The protocol buffers message instance to serialize.
      including_default_value_fields: If True, singular primitive fields,
          repeated fields, and map fields will always be serialized.  If
          False, only serialize non-empty fields.  Singular message fields
          and oneof fields are not affected by this option.
      preserving_proto_field_name: If True, use the original proto field
          names as defined in the .proto file. If False, convert the field
          names to lowerCamelCase.
      indent: The JSON object will be pretty-printed with this indent level.
          An indent level of 0 or negative will only insert newlines.
      sort_keys: If True, then the output will be sorted by field names.
      use_integers_for_enums: If true, print integers instead of enum names.
      descriptor_pool: A Descriptor Pool for resolving types. If None use the
          default.
      float_precision: If set, use this to specify float field valid digits.
      ensure_ascii: If True, strings with non-ASCII characters are escaped.
          If False, Unicode strings are returned unchanged.

    Returns:
      A string containing the JSON formatted protocol buffer message.
    """
    printer = _Printer(
        including_default_value_fields,
        preserving_proto_field_name,
        use_integers_for_enums,
        descriptor_pool,
        float_precision=float_precision)
    return printer.ToJsonString(message, indent, sort_keys, ensure_ascii)


def MessageToDict(
        message,
        including_default_value_fields=False,
        preserving_proto_field_name=False,
        use_integers_for_enums=False,
        descriptor_pool=None,
        float_precision=None):
    """Converts protobuf message to a dictionary.

    When the dictionary is encoded to JSON, it conforms to proto3 JSON spec.

    Args:
      message: The protocol buffers message instance to serialize.
      including_default_value_fields: If True, singular primitive fields,
          repeated fields, and map fields will always be serialized.  If
          False, only serialize non-empty fields.  Singular message fields
          and oneof fields are not affected by this option.
      preserving_proto_field_name: If True, use the original proto field
          names as defined in the .proto file. If False, convert the field
          names to lowerCamelCase.
      use_integers_for_enums: If true, print integers instead of enum names.
      descriptor_pool: A Descriptor Pool for resolving types. If None use the
          default.
      float_precision: If set, use this to specify float field valid digits.

    Returns:
      A dict representation of the protocol buffer message.
    """
    printer = _Printer(
        including_default_value_fields,
        preserving_proto_field_name,
        use_integers_for_enums,
        descriptor_pool,
        float_precision=float_precision)
    # pylint: disable=protected-access
    return printer._MessageToJsonObject(message)


def _IsMapEntry(field):
    return (field.type == descriptor.FieldDescriptor.TYPE_MESSAGE and
            field.message_type.has_options and
            field.message_type.GetOptions().map_entry)


class _Printer(object):
    """JSON format printer for protocol message."""

    def __init__(
            self,
            including_default_value_fields=False,
            preserving_proto_field_name=False,
            use_integers_for_enums=False,
            descriptor_pool=None,
            float_precision=None):
        self.including_default_value_fields = including_default_value_fields
        self.preserving_proto_field_name = preserving_proto_field_name
        self.use_integers_for_enums = use_integers_for_enums
        self.descriptor_pool = descriptor_pool
        if float_precision:
            self.float_format = '.{}g'.format(float_precision)
        else:
            self.float_format = None

    def ToJsonString(self, message, indent, sort_keys, ensure_ascii):
        js = self._MessageToJsonObject(message)
        return json.dumps(
            js, indent=indent, sort_keys=sort_keys, ensure_ascii=ensure_ascii)

    def _MessageToJsonObject(self, message):
        """Converts message to an object according to Proto3 JSON Specification."""
        message_descriptor = message.DESCRIPTOR
        full_name = message_descriptor.full_name
        if _IsWrapperMessage(message_descriptor):
            return self._WrapperMessageToJsonObject(message)
        if full_name in _WKTJSONMETHODS:
            return methodcaller(_WKTJSONMETHODS[full_name][0], message)(self)
        js = {}
        return self._RegularMessageToJsonObject(message, js)

    def _RegularMessageToJsonObject(self, message, js):
        """Converts normal message according to Proto3 JSON Specification."""
        fields = message.ListFields()

        try:
            for field, value in fields:
                if self.preserving_proto_field_name:
                    name = field.name
                else:
                    name = field.json_name
                if _IsMapEntry(field):
                    # Convert a map field.
                    v_field = field.message_type.fields_by_name['value']
                    js_map = {}
                    for key in value:
                        if isinstance(key, bool):
                            if key:
                                recorded_key = 'true'
                            else:
                                recorded_key = 'false'
                        else:
                            recorded_key = str(key)
                        js_map[recorded_key] = self._FieldToJsonObject(
                            v_field, value[key])
                    js[name] = js_map
                elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
                    # Convert a repeated field.
                    js[name] = [self._FieldToJsonObject(field, k)
                                for k in value]
                elif field.is_extension:
                    name = '[%s]' % field.full_name
                    js[name] = self._FieldToJsonObject(field, value)
                else:
                    js[name] = self._FieldToJsonObject(field, value)

            # Serialize default value if including_default_value_fields is True.
            if self.including_default_value_fields:
                message_descriptor = message.DESCRIPTOR
                for field in message_descriptor.fields:
                    # Singular message fields and oneof fields will not be affected.
                    if ((field.label != descriptor.FieldDescriptor.LABEL_REPEATED and
                         field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE) or
                            field.containing_oneof):
                        continue
                    if self.preserving_proto_field_name:
                        name = field.name
                    else:
                        name = field.json_name
                    if name in js:
                        # Skip the field which has been serialized already.
                        continue
                    if _IsMapEntry(field):
                        js[name] = {}
                    elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
                        js[name] = []
                    else:
                        js[name] = self._FieldToJsonObject(field, field.default_value)

        except ValueError as e:
            raise SerializeToJsonError(
                'Failed to serialize {0} field: {1}.'.format(field.name, e))

        return js

    def _FieldToJsonObject(self, field, value):
        """Converts field value according to Proto3 JSON Specification."""
        if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
            return self._MessageToJsonObject(value)
        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM:
            if self.use_integers_for_enums:
                return value
            if field.enum_type.full_name == 'google.protobuf.NullValue':
                return None
            enum_value = field.enum_type.values_by_number.get(value, None)
            if enum_value is not None:
                return enum_value.name
            else:
                if field.file.syntax == 'proto3':
                    return value
                raise SerializeToJsonError('Enum field contains an integer value '
                                           'which can not mapped to an enum value.')
        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING:
            if field.type == descriptor.FieldDescriptor.TYPE_BYTES:
                # Use base64 Data encoding for bytes
                return base64.b64encode(value).decode('utf-8')
            else:
                return value
        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL:
            return bool(value)
        elif field.cpp_type in _INT64_TYPES:
            return str(value)
        elif field.cpp_type in _FLOAT_TYPES:
            if math.isinf(value):
                if value < 0.0:
                    return _NEG_INFINITY
                else:
                    return _INFINITY
            if math.isnan(value):
                return _NAN
            if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_FLOAT:
                if self.float_format:
                    return float(format(value, self.float_format))
                else:
                    return type_checkers.ToShortestFloat(value)

        return value

    def _AnyMessageToJsonObject(self, message):
        """Converts Any message according to Proto3 JSON Specification."""
        if not message.ListFields():
            return {}
        # Must print @type first, use OrderedDict instead of {}
        js = OrderedDict()
        type_url = message.type_url
        js['@type'] = type_url
        sub_message = _CreateMessageFromTypeUrl(type_url, self.descriptor_pool)
        sub_message.ParseFromString(message.value)
        message_descriptor = sub_message.DESCRIPTOR
        full_name = message_descriptor.full_name
        if _IsWrapperMessage(message_descriptor):
            js['value'] = self._WrapperMessageToJsonObject(sub_message)
            return js
        if full_name in _WKTJSONMETHODS:
            js['value'] = methodcaller(_WKTJSONMETHODS[full_name][0],
                                       sub_message)(self)
            return js
        return self._RegularMessageToJsonObject(sub_message, js)

    def _GenericMessageToJsonObject(self, message):
        """Converts message according to Proto3 JSON Specification."""
        # Duration, Timestamp and FieldMask have ToJsonString method to do the
        # convert. Users can also call the method directly.
        return message.ToJsonString()

    def _ValueMessageToJsonObject(self, message):
        """Converts Value message according to Proto3 JSON Specification."""
        which = message.WhichOneof('kind')
        # If the Value message is not set treat as null_value when serialize
        # to JSON. The parse back result will be different from original message.
        if which is None or which == 'null_value':
            return None
        if which == 'list_value':
            return self._ListValueMessageToJsonObject(message.list_value)
        if which == 'struct_value':
            value = message.struct_value
        else:
            value = getattr(message, which)
        oneof_descriptor = message.DESCRIPTOR.fields_by_name[which]
        return self._FieldToJsonObject(oneof_descriptor, value)

    def _ListValueMessageToJsonObject(self, message):
        """Converts ListValue message according to Proto3 JSON Specification."""
        return [self._ValueMessageToJsonObject(value)
                for value in message.values]

    def _StructMessageToJsonObject(self, message):
        """Converts Struct message according to Proto3 JSON Specification."""
        fields = message.fields
        ret = {}
        for key in fields:
            ret[key] = self._ValueMessageToJsonObject(fields[key])
        return ret

    def _WrapperMessageToJsonObject(self, message):
        return self._FieldToJsonObject(
            message.DESCRIPTOR.fields_by_name['value'], message.value)


def _IsWrapperMessage(message_descriptor):
    return message_descriptor.file.name == 'google/protobuf/wrappers.proto'


def _DuplicateChecker(js):
    result = {}
    for name, value in js:
        if name in result:
            raise ParseError('Failed to load JSON: duplicate key {0}.'.format(name))
        result[name] = value
    return result


def _CreateMessageFromTypeUrl(type_url, descriptor_pool):
    """Creates a message from a type URL."""
    db = symbol_database.Default()
    pool = db.pool if descriptor_pool is None else descriptor_pool
    type_name = type_url.split('/')[-1]
    try:
        message_descriptor = pool.FindMessageTypeByName(type_name)
    except KeyError:
        raise TypeError(
            'Can not find message descriptor by type_url: {0}'.format(type_url))
    message_class = db.GetPrototype(message_descriptor)
    return message_class()


def Parse(text,
          message,
          ignore_unknown_fields=False,
          descriptor_pool=None,
          max_recursion_depth=100):
    """Parses a JSON representation of a protocol message into a message.

    Args:
      text: Message JSON representation.
      message: A protocol buffer message to merge into.
      ignore_unknown_fields: If True, do not raise errors for unknown fields.
      descriptor_pool: A Descriptor Pool for resolving types. If None use the
        default.
      max_recursion_depth: max recursion depth of JSON message to be
        deserialized. JSON messages over this depth will fail to be
        deserialized. Default value is 100.

    Returns:
      The same message passed as argument.

    Raises::
      ParseError: On JSON parsing problems.
    """
    if not isinstance(text, str):
        text = text.decode('utf-8')
    try:
        js = json.loads(text, object_pairs_hook=_DuplicateChecker)
    except ValueError as e:
        raise ParseError('Failed to load JSON: {0}.'.format(str(e)))
    return ParseDict(js, message, ignore_unknown_fields, descriptor_pool,
                     max_recursion_depth)


def ParseDict(js_dict,
              message,
              ignore_unknown_fields=False,
              descriptor_pool=None,
              max_recursion_depth=100):
    """Parses a JSON dictionary representation into a message.

    Args:
      js_dict: Dict representation of a JSON message.
      message: A protocol buffer message to merge into.
      ignore_unknown_fields: If True, do not raise errors for unknown fields.
      descriptor_pool: A Descriptor Pool for resolving types. If None use the
        default.
      max_recursion_depth: max recursion depth of JSON message to be
        deserialized. JSON messages over this depth will fail to be
        deserialized. Default value is 100.

    Returns:
      The same message passed as argument.
    """
    parser = _Parser(ignore_unknown_fields, descriptor_pool, max_recursion_depth)
    parser.ConvertMessage(js_dict, message, '')
    return message


_INT_OR_FLOAT = (int, float)


class _Parser(object):
    """JSON format parser for protocol message."""

    def __init__(self, ignore_unknown_fields, descriptor_pool,
                 max_recursion_depth):
        self.ignore_unknown_fields = ignore_unknown_fields
        self.descriptor_pool = descriptor_pool
        self.max_recursion_depth = max_recursion_depth
        self.recursion_depth = 0

    def ConvertMessage(self, value, message, path):
        """Convert a JSON object into a message.

        Args:
          value: A JSON object.
          message: A WKT or regular protocol message to record the data.
          path: parent path to log parse error info.

        Raises:
          ParseError: In case of convert problems.
        """
        self.recursion_depth += 1
        if self.recursion_depth > self.max_recursion_depth:
            raise ParseError('Message too deep. Max recursion depth is {0}'.format(
                self.max_recursion_depth))
        message_descriptor = message.DESCRIPTOR
        full_name = message_descriptor.full_name
        if not path:
            path = message_descriptor.name
        if _IsWrapperMessage(message_descriptor):
            self._ConvertWrapperMessage(value, message, path)
        elif full_name in _WKTJSONMETHODS:
            methodcaller(_WKTJSONMETHODS[full_name][1], value, message, path)(self)
        else:
            self._ConvertFieldValuePair(value, message, path)
        self.recursion_depth -= 1

    def _ConvertFieldValuePair(self, js, message, path):
        """Convert field value pairs into regular message.

        Args:
          js: A JSON object to convert the field value pairs.
          message: A regular protocol message to record the data.
          path: parent path to log parse error info.

        Raises:
          ParseError: In case of problems converting.
        """
        names = []
        message_descriptor = message.DESCRIPTOR
        fields_by_json_name = dict((f.json_name, f)
                                   for f in message_descriptor.fields)
        for name in js:
            try:
                field = fields_by_json_name.get(name, None)
                if not field:
                    field = message_descriptor.fields_by_name.get(name, None)
                if not field and _VALID_EXTENSION_NAME.match(name):
                    if not message_descriptor.is_extendable:
                        raise ParseError(
                            'Message type {0} does not have extensions at {1}'.format(
                                message_descriptor.full_name, path))
                    identifier = name[1:-1]  # strip [] brackets
                    # pylint: disable=protected-access
                    field = message.Extensions._FindExtensionByName(identifier)
                    # pylint: enable=protected-access
                    if not field:
                        # Try looking for extension by the message type name, dropping the
                        # field name following the final . separator in full_name.
                        identifier = '.'.join(identifier.split('.')[:-1])
                        # pylint: disable=protected-access
                        field = message.Extensions._FindExtensionByName(identifier)
                        # pylint: enable=protected-access
                if not field:
                    if self.ignore_unknown_fields:
                        continue
                    raise ParseError(
                        ('Message type "{0}" has no field named "{1}" at "{2}".\n'
                         ' Available Fields(except extensions): "{3}"').format(
                            message_descriptor.full_name, name, path,
                            [f.json_name for f in message_descriptor.fields]))
                if name in names:
                    raise ParseError('Message type "{0}" should not have multiple '
                                     '"{1}" fields at "{2}".'.format(
                        message.DESCRIPTOR.full_name, name, path))
                names.append(name)
                value = js[name]
                # Check no other oneof field is parsed.
                if field.containing_oneof is not None and value is not None:
                    oneof_name = field.containing_oneof.name
                    if oneof_name in names:
                        raise ParseError('Message type "{0}" should not have multiple '
                                         '"{1}" oneof fields at "{2}".'.format(
                            message.DESCRIPTOR.full_name, oneof_name,
                            path))
                    names.append(oneof_name)

                if value is None:
                    if (field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE
                            and field.message_type.full_name == 'google.protobuf.Value'):
                        sub_message = getattr(message, field.name)
                        sub_message.null_value = 0
                    elif (field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM
                          and field.enum_type.full_name == 'google.protobuf.NullValue'):
                        setattr(message, field.name, 0)
                    else:
                        message.ClearField(field.name)
                    continue

                # Parse field value.
                if _IsMapEntry(field):
                    message.ClearField(field.name)
                    self._ConvertMapFieldValue(value, message, field,
                                               '{0}.{1}'.format(path, name))
                elif field.label == descriptor.FieldDescriptor.LABEL_REPEATED:
                    message.ClearField(field.name)
                    if not isinstance(value, list):
                        raise ParseError('repeated field {0} must be in [] which is '
                                         '{1} at {2}'.format(name, value, path))
                    if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
                        # Repeated message field.
                        for index, item in enumerate(value):
                            sub_message = getattr(message, field.name).add()
                            # None is a null_value in Value.
                            if (item is None and
                                    sub_message.DESCRIPTOR.full_name != 'google.protobuf.Value'):
                                raise ParseError('null is not allowed to be used as an element'
                                                 ' in a repeated field at {0}.{1}[{2}]'.format(
                                    path, name, index))
                            self.ConvertMessage(item, sub_message,
                                                '{0}.{1}[{2}]'.format(path, name, index))
                    else:
                        # Repeated scalar field.
                        for index, item in enumerate(value):
                            if item is None:
                                raise ParseError('null is not allowed to be used as an element'
                                                 ' in a repeated field at {0}.{1}[{2}]'.format(
                                    path, name, index))
                            getattr(message, field.name).append(
                                _ConvertScalarFieldValue(
                                    item, field, '{0}.{1}[{2}]'.format(path, name, index)))
                elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
                    if field.is_extension:
                        sub_message = message.Extensions[field]
                    else:
                        sub_message = getattr(message, field.name)
                    sub_message.SetInParent()
                    self.ConvertMessage(value, sub_message, '{0}.{1}'.format(path, name))
                else:
                    if field.is_extension:
                        message.Extensions[field] = _ConvertScalarFieldValue(
                            value, field, '{0}.{1}'.format(path, name))
                    else:
                        setattr(
                            message, field.name,
                            _ConvertScalarFieldValue(value, field,
                                                     '{0}.{1}'.format(path, name)))
            except ParseError as e:
                if field and field.containing_oneof is None:
                    raise ParseError('Failed to parse {0} field: {1}.'.format(name, e))
                else:
                    raise ParseError(str(e))
            except ValueError as e:
                raise ParseError('Failed to parse {0} field: {1}.'.format(name, e))
            except TypeError as e:
                raise ParseError('Failed to parse {0} field: {1}.'.format(name, e))

    def _ConvertAnyMessage(self, value, message, path):
        """Convert a JSON representation into Any message."""
        if isinstance(value, dict) and not value:
            return
        try:
            type_url = value['@type']
        except KeyError:
            raise ParseError(
                '@type is missing when parsing any message at {0}'.format(path))

        try:
            sub_message = _CreateMessageFromTypeUrl(type_url, self.descriptor_pool)
        except TypeError as e:
            raise ParseError('{0} at {1}'.format(e, path))
        message_descriptor = sub_message.DESCRIPTOR
        full_name = message_descriptor.full_name
        if _IsWrapperMessage(message_descriptor):
            self._ConvertWrapperMessage(value['value'], sub_message,
                                        '{0}.value'.format(path))
        elif full_name in _WKTJSONMETHODS:
            methodcaller(_WKTJSONMETHODS[full_name][1], value['value'], sub_message,
                         '{0}.value'.format(path))(
                self)
        else:
            del value['@type']
            self._ConvertFieldValuePair(value, sub_message, path)
            value['@type'] = type_url
        # Sets Any message
        message.value = sub_message.SerializeToString()
        message.type_url = type_url

    def _ConvertGenericMessage(self, value, message, path):
        """Convert a JSON representation into message with FromJsonString."""
        # Duration, Timestamp, FieldMask have a FromJsonString method to do the
        # conversion. Users can also call the method directly.
        try:
            message.FromJsonString(value)
        except ValueError as e:
            raise ParseError('{0} at {1}'.format(e, path))

    def _ConvertValueMessage(self, value, message, path):
        """Convert a JSON representation into Value message."""
        if isinstance(value, dict):
            self._ConvertStructMessage(value, message.struct_value, path)
        elif isinstance(value, list):
            self._ConvertListValueMessage(value, message.list_value, path)
        elif value is None:
            message.null_value = 0
        elif isinstance(value, bool):
            message.bool_value = value
        elif isinstance(value, str):
            message.string_value = value
        elif isinstance(value, _INT_OR_FLOAT):
            message.number_value = value
        else:
            raise ParseError('Value {0} has unexpected type {1} at {2}'.format(
                value, type(value), path))

    def _ConvertListValueMessage(self, value, message, path):
        """Convert a JSON representation into ListValue message."""
        if not isinstance(value, list):
            raise ParseError('ListValue must be in [] which is {0} at {1}'.format(
                value, path))
        message.ClearField('values')
        for index, item in enumerate(value):
            self._ConvertValueMessage(item, message.values.add(),
                                      '{0}[{1}]'.format(path, index))

    def _ConvertStructMessage(self, value, message, path):
        """Convert a JSON representation into Struct message."""
        if not isinstance(value, dict):
            raise ParseError('Struct must be in a dict which is {0} at {1}'.format(
                value, path))
        # Clear will mark the struct as modified so it will be created even if
        # there are no values.
        message.Clear()
        for key in value:
            self._ConvertValueMessage(value[key], message.fields[key],
                                      '{0}.{1}'.format(path, key))
        return

    def _ConvertWrapperMessage(self, value, message, path):
        """Convert a JSON representation into Wrapper message."""
        field = message.DESCRIPTOR.fields_by_name['value']
        setattr(
            message, 'value',
            _ConvertScalarFieldValue(value, field, path='{0}.value'.format(path)))

    def _ConvertMapFieldValue(self, value, message, field, path):
        """Convert map field value for a message map field.

        Args:
          value: A JSON object to convert the map field value.
          message: A protocol message to record the converted data.
          field: The descriptor of the map field to be converted.
          path: parent path to log parse error info.

        Raises:
          ParseError: In case of convert problems.
        """
        if not isinstance(value, dict):
            raise ParseError(
                'Map field {0} must be in a dict which is {1} at {2}'.format(
                    field.name, value, path))
        key_field = field.message_type.fields_by_name['key']
        value_field = field.message_type.fields_by_name['value']
        for key in value:
            key_value = _ConvertScalarFieldValue(key, key_field,
                                                 '{0}.key'.format(path), True)
            if value_field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_MESSAGE:
                self.ConvertMessage(value[key],
                                    getattr(message, field.name)[key_value],
                                    '{0}[{1}]'.format(path, key_value))
            else:
                getattr(message, field.name)[key_value] = _ConvertScalarFieldValue(
                    value[key], value_field, path='{0}[{1}]'.format(path, key_value))


def _ConvertScalarFieldValue(value, field, path, require_str=False):
    """Convert a single scalar field value.

    Args:
      value: A scalar value to convert the scalar field value.
      field: The descriptor of the field to convert.
      path: parent path to log parse error info.
      require_str: If True, the field value must be a str.

    Returns:
      The converted scalar field value

    Raises:
      ParseError: In case of convert problems.
    """
    try:
        if field.cpp_type in _INT_TYPES:
            return _ConvertInteger(value)
        elif field.cpp_type in _FLOAT_TYPES:
            return _ConvertFloat(value, field)
        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_BOOL:
            return _ConvertBool(value, require_str)
        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_STRING:
            if field.type == descriptor.FieldDescriptor.TYPE_BYTES:
                if isinstance(value, str):
                    encoded = value.encode('utf-8')
                else:
                    encoded = value
                # Add extra padding '='
                padded_value = encoded + b'=' * (4 - len(encoded) % 4)
                return base64.urlsafe_b64decode(padded_value)
            else:
                # Checking for unpaired surrogates appears to be unreliable,
                # depending on the specific Python version, so we check manually.
                if _UNPAIRED_SURROGATE_PATTERN.search(value):
                    raise ParseError('Unpaired surrogate')
                return value
        elif field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_ENUM:
            # Convert an enum value.
            enum_value = field.enum_type.values_by_name.get(value, None)
            if enum_value is None:
                try:
                    number = int(value)
                    enum_value = field.enum_type.values_by_number.get(number, None)
                except ValueError:
                    raise ParseError('Invalid enum value {0} for enum type {1}'.format(
                        value, field.enum_type.full_name))
                if enum_value is None:
                    if field.file.syntax == 'proto3':
                        # Proto3 accepts unknown enums.
                        return number
                    raise ParseError('Invalid enum value {0} for enum type {1}'.format(
                        value, field.enum_type.full_name))
            return enum_value.number
    except ParseError as e:
        raise ParseError('{0} at {1}'.format(e, path))


def _ConvertInteger(value):
    """Convert an integer.

    Args:
      value: A scalar value to convert.

    Returns:
      The integer value.

    Raises:
      ParseError: If an integer couldn't be consumed.
    """
    if isinstance(value, float) and not value.is_integer():
        raise ParseError('Couldn\'t parse integer: {0}'.format(value))

    if isinstance(value, str) and value.find(' ') != -1:
        raise ParseError('Couldn\'t parse integer: "{0}"'.format(value))

    if isinstance(value, bool):
        raise ParseError('Bool value {0} is not acceptable for '
                         'integer field'.format(value))

    return int(value)


def _ConvertFloat(value, field):
    """Convert an floating point number."""
    if isinstance(value, float):
        if math.isnan(value):
            raise ParseError('Couldn\'t parse NaN, use quoted "NaN" instead')
        if math.isinf(value):
            if value > 0:
                raise ParseError('Couldn\'t parse Infinity or value too large, '
                                 'use quoted "Infinity" instead')
            else:
                raise ParseError('Couldn\'t parse -Infinity or value too small, '
                                 'use quoted "-Infinity" instead')
        if field.cpp_type == descriptor.FieldDescriptor.CPPTYPE_FLOAT:
            # pylint: disable=protected-access
            if value > type_checkers._FLOAT_MAX:
                raise ParseError('Float value too large')
            # pylint: disable=protected-access
            if value < type_checkers._FLOAT_MIN:
                raise ParseError('Float value too small')
    if value == 'nan':
        raise ParseError('Couldn\'t parse float "nan", use "NaN" instead')
    try:
        # Assume Python compatible syntax.
        return float(value)
    except ValueError:
        # Check alternative spellings.
        if value == _NEG_INFINITY:
            return float('-inf')
        elif value == _INFINITY:
            return float('inf')
        elif value == _NAN:
            return float('nan')
        else:
            raise ParseError('Couldn\'t parse float: {0}'.format(value))


def _ConvertBool(value, require_str):
    """Convert a boolean value.

    Args:
      value: A scalar value to convert.
      require_str: If True, value must be a str.

    Returns:
      The bool parsed.

    Raises:
      ParseError: If a boolean value couldn't be consumed.
    """
    if require_str:
        if value == 'true':
            return True
        elif value == 'false':
            return False
        else:
            raise ParseError('Expected "true" or "false", not {0}'.format(value))

    if not isinstance(value, bool):
        raise ParseError('Expected true or false without quotes')
    return value


_WKTJSONMETHODS = {
    'google.protobuf.Any': ['_AnyMessageToJsonObject',
                            '_ConvertAnyMessage'],
    'google.protobuf.Duration': ['_GenericMessageToJsonObject',
                                 '_ConvertGenericMessage'],
    'google.protobuf.FieldMask': ['_GenericMessageToJsonObject',
                                  '_ConvertGenericMessage'],
    'google.protobuf.ListValue': ['_ListValueMessageToJsonObject',
                                  '_ConvertListValueMessage'],
    'google.protobuf.Struct': ['_StructMessageToJsonObject',
                               '_ConvertStructMessage'],
    'google.protobuf.Timestamp': ['_GenericMessageToJsonObject',
                                  '_ConvertGenericMessage'],
    'google.protobuf.Value': ['_ValueMessageToJsonObject',
                              '_ConvertValueMessage']
}
